It is known to use a video recording and reproducing apparatus, such as a digital video tape-recorder, for recording received data of digital broadcasting signals in a bit stream form. FIG. 2 illustrates transponders in relation to programs and elementary streams (ES). As shown in FIG. 2, a plurality of programs for digital broadcasting are multiplexed in one transponder (equivalent to a channel in the analog broadcasting). One program consists of at least one elementary stream. In a conventional video recording and reproducing apparatus such as a digital video tape-recorder, a stream of bits of data about a program(s) specified by a user only are recorded while data of any other programs are deleted for minimizing the bit rate for recording.
FIG. 3 is a block diagram showing an arrangement of a conventional video recording and reproducing apparatus. The conventional video recording and reproducing apparatus comprises:
(a) tuner 21 for converting data of a digital broadcasting signal in a transponder into a stream of bits which are then outputted;
(b) program selector 22 for deleting bits other than of a program selected by the user from the stream of bits released from tuner 21;
(c) decoder 23 for separating the stream of bits received from program selector 22 into elementary streams, namely video data and audio data, and decoding the elementary streams to a video signal and an audio signal;
(d) output section 24 for transferring the video signal and the audio signal received from decoder 23 to an external audio-video apparatus such as a television receiver; and
(e) recorder/player 25 for recording the stream of bits released from program selector 22.
An action of the conventional video recording and reproducing apparatus having the foregoing arrangement is now explained. When a particular program is specified by the user, tuner 21 tunes in to a broadcast transponder which is including the program and converts digital data of the program received from the transponder into a stream of bits which are then transferred to program selector 22. Program selector 22 picks up the stream of bits data of the program specified by the user and feeds decoder 23 with the program as a stream of data excluding any other data. Decoder 23 divides the stream of bits received from program selector 22 into ES of bits, namely video data and audio data, which are then decoded to a video signal and an audio signal. The signals reproduced by decoder 23 are transferred to output section 24 from which they are distributed to an external audio-video apparatus such as a television receiver.
Also, the data of the program specified by the user and separated from the intercepted signal, unwanted data hence deleted, is transferred as a stream of bits from program selector 22 to recorder/player 25. The stream of bits of the program data are then recorded by recorder/player 25.
The conventional apparatus however fails to check the number of ES of bits before recording. Accordingly, if the apparatus is capable of recording only twelve ES of bits at maximum because of the performance of its LSI and the number of ES of bits received is greater than twelve, its recording operation may be carried out at random regardless of the direction of the user.